SNOSB24C October   2008  – November 2025 LM5576-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Shutdown / Standby
      2. 6.3.2 Soft Start
      3. 6.3.3 Thermal Protection
    4. 6.4 Device Functional Modes
      1. 6.4.1 High Voltage Start-Up Regulator
      2. 6.4.2 Oscillator and Sync Capability
      3. 6.4.3 Error Amplifier and PWM Comparator
      4. 6.4.4 Ramp Generator
      5. 6.4.5 Maximum Duty Cycle / Input Dropout Voltage
      6. 6.4.6 Boost Pin
      7. 6.4.7 Current Limit
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Bias Power Dissipation Reduction
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1  Custom Design With WEBENCH® Tools
        2. 7.2.2.2  External Components
        3. 7.2.2.3  R3 (RT)
        4. 7.2.2.4  L1
        5. 7.2.2.5  C3 (CRAMP)
        6. 7.2.2.6  C9, C10
        7. 7.2.2.7  D1
        8. 7.2.2.8  C1, C2
        9. 7.2.2.9  C8
        10. 7.2.2.10 C7
        11. 7.2.2.11 C4
        12. 7.2.2.12 R5, R6
        13. 7.2.2.13 R1, R2, C12
        14. 7.2.2.14 R7, C11
        15. 7.2.2.15 R4, C5, C6
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
      3. 7.4.3 Power Dissipation
      4. 7.4.4 Thermal Considerations
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 Custom Design With WEBENCH® Tools
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

7.2.2.12 R5, R6

R5 and R6 set the output voltage level. Use Equation 15 to calculate the ratio of these resistors.

Equation 15. R5/R6 = (VOUT / 1.225V) – 1

For a 5V output, the R5/R6 ratio calculates to 3.082. The resistors must be chosen from standard value resistors. A good starting point is selection in the range of 1.0kΩ to 10kΩ. Values of 5.11kΩ for R5, and 1.65kΩ for R6 were selected.